Many studies have investigated the effect of emulsifiers on the oxidative stability of oil-in-water (O/W)
emulsions. A better oxidative stability of surfactant-stabilised O/W emulsions as compared to proteinstabilised
emulsions has been recently shown in conditions when the major part of the emulsifier is
adsorbed at the oil–water interface and oxidation is induced by ironethylenediaminetetraacetic acid
(EDTA) complex. In this work, the contribution of the interfacial layer to the oxidation of emulsified lipids
is investigated under various incubation conditions, involving different oxidation mechanisms. O/W
emulsions were formulated at pH6.7 with limited amounts of emulsifiers in the aqueous phase.
Emulsions were incubated either at 33 C without initiator at 25 C in the presence of iron/ascorbate,
metmyoglobin or 2,20-azobis(2-amidinopropane)-dihydrochloride (AAPH). Oxygen uptake and volatile
compound formation confirmed that protein-stabilised emulsions are less oxidatively stable than Tween
20-stabilised ones. This work also shows complex oxidative interrelationships between oxidation
initiator and certain proteins, such as b-casein and bovine serum albumin